Stable hydrogen peroxid.



unirni STATES PATENT orinon.

OTTO IIIEBKNECHT, OF FRANKEORT-ON-THE-MAIN, GERMANY, ASSIGNOR TO THEROESSLER & HASSL ACHER CHEMICAL (70., OF NEW YORK, N. Y., A. CORPORATIONon NEW YORK.

STABLE HYDROGEN PEBOXID.

No Drawing.

Specification of Letters ratent.

Application filed November 17, 1911.

Patented Apr. 8, 1913. Serial No. 660,785.

' peroxid.

Heretofore strong mineral acids have been chiefly used in order torender hydrogen overcome the difficulties and disadvantages peroxidsolutions stable, for instance, a certaln quantlty of phosphoric acidhas been added to the hydrogen peroxid. The stability thus obtained ishowever of limitedduration, as, after a short time, appreciable lossesof active oxygen takes place. The addition of mineral acid has, however,been considered necessary, as, without it, a quicker decomposition takesplace. The action of the mineral acid is accounted for by the strongerelectrolytic dissociation of the mineral acid, which lessens thedissociation of the exceptionally weak acid hydrogen peroxid and thusprevents decomposition.

The comparatively low degree of stability of the present hydrogenperox'id solutions, even with the addition of mineral acids, has beencommercially a great drawback, and medically the use of such acidhydrogen peroxid solutions is greatly retarded on account of causingirritation.

There is in the market a 30% chemically pure hydrogen peroxid which,however, in order to preserve its stability, must be kept in paraffinedbottles. This product has to be diluted before using and then undergoesthe quick decomposition hereinabove described. v

The object of. the present invent-ion is to patents have been made. Inone of these prior applications for Letters Patent, Serial No. 611,587,filed March 11th, 1911, I have stated that the addition of a very smallguantityof sulfanilic acid to an aqueous hyrogen peroxid solution.renders the same stable.

On further investigation I have foundv out ters that the drawbacksconnected with the use of a mineral acid, such as sulfuric acid, may begreatly reduced if the sulfuric acid is combined with an aromatichydrocarbon into a so-called aromatic sulfonic acid; for instance, incase of benzene and sulfuric acid forming benzene-sulfonic acid; and although said aromatic sulfonic acids are -much less dissociatedelectrolytically than sulfuric acid, I have furthermore discovered thatbesides benzene-sulfonic acid, also other similar acids exert the samestabilizing effect on an aqueous hydrogen peroxid solutio n as forinstance, naphthalene-sulfonic acid, anthracene-sulfonic acid, etc. aswell as the corresponding disulfonic acids of these aromatichydrocarbons. The addition of a very small quantity of any of sucharomatic acids to an aqueous'solution'of hydrogen peroxid, prepared inany way, renders the same stable. The following example serves as anelucidation of my process: 2 grams of benzene-sulfonic acid may bedissolved in one liter of a 20% aqueous hydrogen 'peroxid solution, thusrendering the solutlon stable,

while a plain hydrogen peroxid solution of the same strength without thebenzene-sulfonic acid easily undergoes decomposition.

The action of the aromatic sulfonic acids I portion of any of thearomatic sulfonic acidsto be used, various proportions of such acidsproducing the results set forth when added tohydrogen peroxid solutionsof various degrees of concentration.

I What I claim and desire to secure by Let- P tent is:' v hydrogenperoxid solutlon contama substance which in turn contains a ing bodyformed by the combination of sulfuric acid with an aromatic hydrocarbon.

2. A hydrogen peroxid solutlon contaming benzene-sulfomc acid,

In testimony whereof I have signed this specification in the presence oftwo subscribing, witnesses.

. OTTO LIEBKNECHT. Witnesses:

JEAN GRU'ND,

CA L GRUND.

